Chronic baroreflex activation persistently lowers blood pressure in resistant hypertension: single-center experience with the barostim neo system

Abstract

Background: Hypertension (HTN) continues to pose a significant healthcare challenge. Medical therapies are useful for improving outcomes but have significant limitations such as side effects, inconsistent patient compliance and incomplete control of blood pressure (BP). Nonpharmacologic therapies have recently become commercially available that lower BP adjunctive to medical therapy and are promising to reduce the HTN-related morbidity and mortality. Chronic activation of the baroreflex has been shown to reduce BP for >4 years using the first-generation device (Rheos) and 6 months using the next-generation system (Barostim neo), which requires only unilateral stimulation and therefore allows considerably less invasive implantation. Here, we report our long-term, single-center results for 7 patients over 12 months with the Barostim neo device. Methods: Resistant HTN patients were enrolled in an open-label, single-arm evaluation of Barostim neo. Eligibility criteria required systolic BP ≥ 140 mmHg despite stable (≥4 weeks) medical therapy consisting of ≥3 medications including at least one diuretic. Patients with secondary HTN, severe chronic kidney disease, advanced carotid atherosclerosis or baroreflex failure were excluded. Results: Seven patients were enrolled including 3 women and 2 with previous renal nerve ablation. The mean office cuff blood pressure at enrollment was 183.4±28.3mmHg (systolic blood pressure;SBP) over 97.4±19.1mmHg (diastolic blood pressure;DBP) with an average of 4.7±1.4 antihypertensive drugs. 6 months after activation of the Barostim neo device the blood pressure was reduced to 150.7±50.9mmHg (SBP; p=0.06) over 85.0±35.7mmHg (DBP; p=0.28) with an average of 5.4±1.0 (p=0.22) antihypertensive drugs. After 12 months blood pressure remained lowered at 157.1±55.5mmHg (SBP; p=0.12) over 84.0±30.5mmHg (DBP; p=0.11) with an average of 4.6±1.9 (p=0.86) antihypertensive drugs. At screening 1 patient had a SBP between 140 and 160mmHg, two patients had SBPs 180mmHg. After 6 months 4 patients (=57%) reached a SBP below 140mmHg, which proved to be consistent on the twelve-month evaluation. During the 12 months of follow-up only one serious adverse event, a device pocket haematoma, occurred and resolved completely. Conclusions: Throughout 12 months of follow-up unilateral baroreflex activation therapy reduces BP consistently in patients with resistant HTN without exposing patients to excessive risks. Therefore baroreflex activation therapy should be considered as a treatment option for patients with resistant HTN after exclusion of secondary HTN.